Method of making lamp sockets



Dec. 2, 1924. 1,517,524

G. ARRAS ET AL METHOD OF- MAKING LAMP SOCKETS Filed Deo. 31. 1920 2 shura-sheet 1 bec. 2, 1924. 1,517,524

G. ARRAS ET AL METHOD OF MAKING LAMP SOCKETS Filed Dec. 5l. 1920 2 SheOtB-Sheet 2 Patented. Dec. 2, 1924.

ARRASAND DWIGHT E. WORRELL, y(JF CHICAGO, ILLINOIS.

METHOD OF MAKINGv LAMP -SOGKETS.

Application nled December 31 i920. Serial No. 434,207.

To all rwhom t may concern;

Be it known that we, GEORGE ARRAS and e DWIGHT E. WORRELL, citizens of the United Vis States, residing at Chicago; in thecounty of Cook and State of. Illinois, have invented certainl new and useful Improvementsin Methods of Making ,Lamp Sockets, of which the following. is a Specification.

, This invention relates to the method of making a moulded lamp socket composed' of a plurality of parts, and among the objects of the invention are: tomake a moulded lam socket of av plurality ofparts in which ihe amp` terminals are easily accessible; to

make a mp socket in which [the arts are 'easily separated; to provide means oryinset.-

ting conductors at the time the Aparts are moulded; to mould thevarious parts of the socket at the same time; to use 4a. minimum number of dies i'n moulding the socket parts; and in general, to-producethe socket herein shown and described.

In the accompanying drawings, Fig. 1 is a sectional view illustrating vthe method and apparatus for making a socket of this kind; Fig. 2 is` a top view of one of the die parts; Fig. 3 is a view of the die for forming the e outside of the principal socket member; Fi

4 is a view of the diefor making the insi e of the socket member; Fig. 5 is a side elevation of the completely formed socket; Fig. 6 is aviewof the-underside of the socket cap taken on thenline 6-.6 of Fi 5`; Fig. 't'` is a sectional view taken on the 'line 7''7 of. Fig. 6 of a completed socket and cap; Fig. 8 is a top view o the socket member taken on the line 8--8 of Fig.- 7; Fig. 9 is an'enlarged sectional View showing the knockout thread l modified forming parte; and Fig. 10 illustrates a orm of the cap.

Moulded sockets of porcelain or other insulating materials are well known and commonly used, and .the present invention/relates to any insulating compound which can be moulded when subjected to' heat and pressure or either of them, the present socket being formed. of a substance somewhat similar in appearance to hard rubber and purchasable in powdered formready for use;

This lamp socketas iillustr'atedby Figs.

' 5, 6 and 7 comprises asocket member 1, having a hollowed out portion 2 into whichthe contact extremity of ani'electric lampris -inserted, and having a cap 3 which covers and protects the terminal connections for the socket and is attached to the socket Amember v'portions 8 formed up out of the material of .the socket itself so that they together with the strip 5` form the en aging and holding and contact means for a amp'socket inserted in the socket member. .The central contact screw, 4 ,forms the central terminal for a lamp inserted in the' socket member so that both connections are made for a lam In'the cap 3, as clearly shown inll s 6 and 7, there isatransverse partition 9 w ich normally separates the ordinary opposite apertures 10 in the edge of the cap, and at the center of the partition is an enlargement 11 inv which' is imbedded one extremity, of a conductor 4'12 into which the fastening screw 4 is inserted. This conductor strip extends from the central partition into the side wall of the cap, and beneath the lconductor is an abutment .1B-to assist in'holding the conductor in place. Between the partition enlargement 11 and the side wallof the cap 3, a contact screw 14 is inserted into'the conductor 12 and forms a bindingjpostfor one of the conductors of the lamp.

In practice,`a conductor 15 is connected to the contact screw 7 at the 'top of the socket member before the cap` is placed in o stion and another conductor 16 is connecte by the `binding screw,14 tothe contactpiece 12 of the cap. This conductor-16 extends through the o ening 10 on its side of the partition y9, and tlieother conductor. 15 extends through the'other cap opening 10 on the other side of the partition 9. Thus the lamp terminal connections are 'separatedby the partition 9, greatly,lessening the danger for a' short circuit between them. In order to assemble the vparts after the cap is in position, it is only necessary to insert the screw 4 from the inside of the socket member into the contact kmember 12 o'f the-cap through the enlargeintendedV bothto properly position the cap by entering-the opposite notches 10 thereof, and also to partial y lill the opening made thereby, making the conductors fit more closely in the notches. Opposite projections 18 are commonly formed on a shoulder 19 at the outside of the socket member for positioning the socket member in a cover plate with which 'a socket of this kind is commonly used.

If desired, the cap 3l may be formed with thin knockout portions 20 opposite the notches 10, so that a air of, notches 10 will be provided on each side ofthe partition, as shown more clearly in Fig..10. This will permit the cap and socket member to be connected to conductors running through the cap and not to the conductor lterminals as shown in Fig. 7

In order to form a two part conductor of this type it is customary to employ an upper and a lower die member for each part. The present invention contemplates the use of one die member for the .outer part of one piece and for the inner part of the other piece. This might be continued in the same way, the result being only one more die part than the number of pieces to be moulded will be required. The advantage of this is that the pieces thus moulded will be more uniform and of the same diameter and consistency. In carrying out this invention, a three part mould is employed as conventionally .shown in Fig. 1, in which the die parts 21, 22 and 23 are shown in a guide or container 24 receiving pgessure from a presser foot 25. At the outside of the guide 24 is ya shell 26 surrounding which are electric heating coils 27 and a cooling coil 28.

The socket member 1 is formed between the die parts 22' and 23 and the cap member is formed between. the diel parts 21 and 22, the dies being formed with the y roper recesses and projections to form t e various features of the socket parts which is well known in practice,fand will not be specifically enumerated. However, in moulding the .contact pieces 12 and strip 5 within the cap and socket members respectively, and in formingv the thread portions within the socket member, a somewhat different construction is employed. In the central die member 22 is a bore 28 extendin between the upper and -lower die pieces an into this bore a removable 'pieve 29 is inserted which has a reduced stem 30 at its lower end for forming the opening in the top of the socket member 1 which receives the screw 4. At the other end of the piece 29 is a shoulder 31 which forms the outer face of the central partition 11 in the cap, and then a reduced portion 32 which forms an unthreaded lopening in the partition 11 for the free insertion of screw 4 after cap is formed, .and1 at the end va reduced stem 33 over whig'rh the lthreaded conductor piece 12 is inserted, the4 stem extending beyond the contact piece into the material of the cap to aiord a space therein for the insertion of the screw 4, as shown in Fig. 7. Imio'rder that the threads for receiving the screw 14 of the contact piece 12 may not be filled with the moulded insulating material of the cap, the screw 14 is threaded through the piece and placed in position on top of the die 22 when the die is being set for the moulding operation, as shown more clearly in Fig. 2, the head of the screw being inserted in an opening provided for it in the top of thedie 22. j

It is customary to cast a designating mark inthe edge of the socket member, to indicate the origin thereof, or to designate the capacity ,for service of lthe socket member. Such indication, however, would be defaced it were necessary to remove the socket member 1 from the die bv unscrew'ing it therefrom as will be evident from Fig. 4, as the indicating characters. 34 are formed in the face of the die 23. The threadforming portions of the die are therefore made removable, as shown more clearly in Figs. 4 and 9, with the exception of course, of the contact strip '5 which isv moulded into the material of the socket. The crimped thread strip 5 is held in place on the lower die member 23 by means of a projection 35 which extends through the threaded opening in the bent portion 6 of this strip, the crimped portion being seated in a shallow recess 36 in the side of the die. The other thread ortions 8 in each socket member are forme by knockout pieces 37 which are each seated in a Side recess 38 of the lower die member 23, and each thread forming piece 37 has a reduced projection 39 which extends through a corresponding opening 40 in the die member 28. The outer face of each 'knockout piece 37 hasa wavy outline 41 to form a corresponding thread portion in the inside wall of the socket member 1 which projects at least the depth of the thread from the inside face of the socket member. rThis makes the thread portion stand out on the inside of the socket member, and of course, the different thread portions must present the proper portion of thethread to engage a socket there- 1n.

When the socket member 1 is completely formedin the die it is desired to remove the socket from the lower die member 23, it is obvious that the socket member cannot be turned or threaded oli' of the die member 2 3 without defacing the letters formed by the characters 34. The knockout pieces 37 are therefore provided which may be pressed outwardly and upwardly from the die member 28 carrying with them the formed socket member, and after the extensions 39 slip out of the sockets or recesses 40 therefor, the knockout pieces can be removed or separat- .ed from the form socket member, leaving icsthe threaded portions 8 undamaged, and carrying the crimped conductor strlp 5 with the socket in which it is moulded.

In carrying out thisA invention, a measured quantity of the material of which the socket parts are made is placed between the die members as they are assembled. Heat or pressure, or both, is applied to form the socket parts after which the dies and socket parts may be` tempered or cooled by means of a coil 28. The dies are separated and the socket parts are removed therefrom as described. It is obvious that although the dies for a single socket only is shown the same general method may be employed in making any number of sockets at the same time. After the socket parts are for-med it is necessary only to insert the contact screw 7 throu h the top of the socket member 1 and into t e contact strip 5 to connect a conductor' thereto, and to connect ak conductor by means of the contact screw14 ,to the conductor 12. The cap is attached to the socket member by means of a'screw 4 andthe entire socket is then in condition to receive an electric lamp. In order to separate the socket parts, it is -necessary only to remove the lamp and the screw 4, whereupon both of the circuit terminals of the socket parts are freely accessible.

We claim:

l. The method of making a multi-part.

moulded socket between co-operating die members for forming the socket parts at the same time, there being one more die member than the number of socket parts, which consists in introducing between the die members a measured quantity of insulating material which hardens when subject to heat and pressure, and in moulding into each of the socket parts thus formed a conductor which becomes a part of the socket thus formed.

2. The method of making a two part socket by means of an upper, lower and an intermediate -die member, which consists in introducing between the intermediate and each of the other die members a measured quantity of insulating material, in supporting an electrical conductor by means of the die which becomes moulded into the material of the socket, and isremoved therewith, and in applying heat and pressure to form the socket parts.

3. The method of moulding -a two part socket, with up r, lower and intermediate die members o substantially the same ex: ternal size, which consists in introducing ameasured quantity of insulating material between adjacent dies, ininserting the die threaded through the electrical conductor, n

so that as the insulating material is moulded about the conductor, the conductor becomes embedded in the socket part and the head of the screw which is lthreaded into the conductor projects from the face of the contact, and the threaded portion of the s'crew. prevents the insulating material from filling the threads in the electrical conductor.

5. The method of moulding a socket part with threaded portion therein which consists in providing one of the die parts with removable thread forming portions which are removable with the socket when i-t is formed so that the threads are not broken in separating the socket from the die, and in then separating the thread forming parts and re-inserting them in the die before the next socket part is formed.

6. The method of moulding a socket part having threaded portions therein and lindicating characters in one face at right angles to the threads, which consists in providingv one of the die parts with thread forming pieces, and in removing the formed socket part and the said pieces together from theI die part directly away from the characters formed therein, so that the characters will not be distorted or broken, and in thereafter loosening the threadfforming pieces from the formed socket so that the thread portions are not broken thereby.

7. The method of moulding a lamp socket in a die with removable thread forming portions, which consists in'applying to this ldie a crimped conductorastrip which is seated in the recess in the `di`e part so that the crimped portion forms projecting threads in the socket member, in moulding the insulation about the conductor -member, in

separating the part thus formed from tho die by removing with it the'thread forming pieces and the crimped conductor piece from the diev and in loosening the thread forming pieces from the socket member after it is removed thereby.

` GEORGE ARRAS.

DWIGHT E. WORRELL. 

